Running a Usability Test
Some common moderating techniques include:
Concurrent Think Aloud (CTA) is used to understand participants’ thoughts as they interact with a product by having them think aloud while they work. The goal is to encourage participants to keep a running stream of consciousness as they work.
In Retrospective Think Aloud (RTA), the moderator asks participants to retrace their steps when the session is complete. Often participants watch a video replay of their actions, which may or may not contain eye-gaze patterns.
Concurrent Probing (CP) requires that as participants work on tasks—when they say something interesting or do something unique, the researcher asks follow-up questions.
Retrospective Probing (RP) requires waiting until the session is complete and then asking questions about the participant’s thoughts and actions. Researchers often use RP in conjunction with other methods—as the participant makes comments or actions, the researcher takes notes and follows up with additional questions at the end of the session.
Best Practices
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Remember that you are testing the site not the users.
Remain neutral – you are there to listen and watch. If the participant asks a question, reply with “What do you think?” or “I am interested in what you would do.”
http://www.usability.gov/how-to-and-tools/methods/running-usability-tests.html
